Study Finds Fivefold Increase In Alzheimer's Deaths: Why It Matters

Consider a hypothetical 70-year-old woman; she could be your mother, your sister, your wife. Call her Margaret. She’s becoming ever-more forgetful; one day she gets lost on her way home from the grocery store. A neurologist diagnoses Alzheimer’s.

Over the next five years, Margaret’s thinking continues to decline. She speaks less, confuses words, falls often. She needs a wheelchair, becomes incontinent. No longer able to manage her care, you move her to a nursing home. A year later, the disease has spread to the part of Margaret’s brain that controls swallowing; she has difficulty eating. Because of this she “aspirates” her food — bits of it enter her lungs, and Margaret develops pneumonia. Within weeks, her lungs stop working, and Margaret dies.

Margaret’s story is a difficult one, but common. It also illustrates a conundrum: Did Margaret die of pneumonia, or Alzheimer’s?

On some level, the answer doesn't matter much: death is death. But as a matter of public health, the answer is deeply important: funding for medical research, new treatments and ultimately, someday, a cure, tends to flow toward the most widespread and deadly diseases. That's why a new study out this week is getting so much attention; should its findings become widely accepted, they could substantially increase the pace and effectiveness of Alzheimer’s research in the U.S.

Massive Underreporting

The study, published Wednesday in the journal Neurology, confirmed what clinicians and researchers have long assumed: Alzheimer's deaths have been greatly underreported.

The research found that 500,000 people die each year from Alzheimer's — more than five times the number most recently reported by the CDC. That makes Alzheimer’s the third leading cause of death in the United States, after heart disease and cancer. Currently the CDC ranks Alzheimer’s sixth as a cause of mortality, with 84,000 deaths reported on death certificates.

The new report’s fuller accounting of Alzheimer’s deaths reinforces a basic but frequently overlooked fact: The illness is entirely fatal. A progressive brain disease that gradually impairs memory, reasoning and personality, Alzheimer’s eventually damages all brain functions, so that even walking, eating and breathing become impossible. Alzheimer’s kills because the brain is no longer able to keep the body alive.

Yet many people think of Alzheimer’s as something you live with — a terrible disease that severely compromises your quality of life, yes, but not truly deadly. “Because Alzheimer’s can be a slow, insidious process, which may play out over many years-- sometimes even a decade or more — people often don’t realize that it is a fatal condition,” says Ronald Petersen, M.D., director of the Mayo Clinic’s Alzheimer's Disease Research Center.

The new study’s lead author, Bryan James, agrees. “People say, ‘Oh, you’re just talking about people who died with Alzheimer’s. But they really died of some other cause,’” says James, an epidemiologist with Rush University’s Alzheimer's Disease Center. “That kind of frustrates” James and his fellow researchers, he says, “because the other cause you’re talking about” — like pneumonia, the most common immediate cause of death in Alzheimer’s patients, as in Margaret’s case — “might not have happened had they not had Alzheimer’s in the first place.”

To more adequately measure Alzheimer’s as a cause of death, James and his fellow researchers analyzed data from two groups of people — 2500 total participants — who’d agreed to annual cognitive tests, and to brain autopsy after their deaths. The scientists compared death rates between those diagnosed with Alzheimer’s and those who were free of the disease. The team found that a person with a diagnosis of Alzheimer’s was three to four times more likely to die within a given period than was a person of the same age who had not been diagnosed with the disease.

Using this death rate, James and his colleagues extrapolated the number of deaths caused annually by Alzheimer’s to the American population — and came up with the new, dramatically higher number the study reports.

How We Got Here: Doctors, Diagnoses And Death Certificates

Why such a disparity between the two figures? The answer is two-fold.

Alzheimer’s is under-diagnosed: As many as half of people who develop Alzheimer’s never receive diagnoses, studies have found. This is in part because strategies for determining Alzheimer’s are much less established in medical practice than are other diagnostic methods. Many doctors who aren’t trained in geriatrics or in neurology, for example, “don’t know exactly how to go about [testing],” James says. These doctors may also never refer their patients to specialists who do practice the thorough cognitive testing that can reliably identify Alzheimer’s.

Other dynamics add to the problem: Older people may avoid visiting doctors, or not have easy access to them. Petersen finds that physicians who conclude that their patients have Alzheimer’s sometimes don’t record the diagnoses in their patients’ charts; the omissions may be an effort, Petersen says, to protect patients and/or their families from painful news. Other patients and families don’t seek testing because they view declining cognitive abilities as a normal part of getting old. Dementia is not a normal sign of aging, James says, but that it is remains a fairly common myth.

Death certificate data is unreliable: Another reason for the undercounting of Alzheimer’s deaths lies in the American system for recording deaths. The CDC bases its cause-of-death counts on what clinicians report in death certificates. A doctor must certify each death and record its immediate cause. Elsewhere on the form, he or she also cites underlying conditions that contributed to this immediate cause.

Filling out death certificates is not a task that doctors relish, nor devote a lot of time to, says David Reuben, a geriatrician and researcher at UCLA. “It’s just more work for the doc,” he says. Thus death certificates, Reuben says, are “notoriously inaccurate.” This is especially true for Alzheimer’s. In the hypothetical case of Margaret, for example, a physician or nurse would very likely list pneumonia as the immediate cause of death. He or she may not mention Alzheimer’s at all — especially if the clinician on call doesn’t know Margaret, is unaware of her history, or is simply busy.

This practice, though understandable, has indirectly impeded funding for Alzheimer's research.

Following The Money

The federal government spends on Alzheimer’s research only about a tenth what it does on cancer research. This, despite findings that Alzheimer’s costs society about as much as cancer does — some $200 billion a year. Meanwhile outcomes for cancer are improving in the U.S., due largely to better treatments. Yet deaths from Alzheimer’s disease have risen 68 percent since 2000, according to the Alzheimer’s Association.

By 2050, the organization predicts, the number of people with Alzheimer’s will triple, and costs for Alzheimer’s care will reach a trillion dollars.

This new study, then, has advocates hoping that its more accurate picture of Alzheimer’s deaths will boost their arguments for funding — and change the politics of the disease by raising awareness of Alzheimer's deadly effects. (Reuben, for one, recalls that funding for AIDS soared in the face of greater public concern.) The Alzheimer’s death-rate study, Petersen asserts, “highlights the fact that Alzheimer’s is as important, when you come to talk about mortality, as heart disease and cancer.” He and others hope that money, better treatments, even prevention, will follow.

Nell Lake, a journalist and magazine writer, wrote the new book, “The Caregivers: A Support Group’s Stories of Slow Loss, Courage And Love” in which she chronicles the lives of family caregivers over two years. She lives with her family in Western Mass.